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2011 Production and Geologic Conditions <br />The Bowie No. 1 Mine suspended operations during December, 1997 and remained <br />idle throughout the calendar year. The mine has been reclaimed. <br />Operation Unit Descriptions <br />Bowie No. 1 Mine has no operating units to report on during the calendar year. <br />Subsidence Impacts - 2011 <br />Selected subsidence monitoring stations established over the Pitkin Mesa pipeline were <br />monitored in July and December of 2011. <br />Wide- Spaced Monitoring Grid Station Summary <br />Through technical revision number 45, the DRMS approved a reduction in subsidence <br />monitoring. The wide spaced subsidence monuments, Sites 6, 14, 15, 16, DH 55, DH <br />65, DH 66, DH 68, 81, 82, 83 and 95 were not monitored during the year. <br />Pitkin Mesa Pipeline <br />Seven subsidence monitoring stations were established at locations along the Pitkin <br />Mesa Pipeline which overlies Panel C. Panel C development commenced in October <br />with twenty -four crosscuts completed by January 1, 1993. Panel C was mined utilizing <br />a partial extraction design intended to preclude the development of subsidence in order <br />to protect the pipeline. The subsidence monitoring stations along the pipeline are <br />depicted on Map No. 2 -5. The stations were surveyed twice in 2011; July 8th and <br />December 16th. The results of this survey are appended to this report. The 2011 <br />survey was conducted by Cragg Surveying. The Cragg survey will provide consistent <br />survey values in the future, which will show that this area is stable. Surveys will <br />continue approximately semi - annually until stability is documented. <br />Visual Monitoring 2011 <br />Visual subsidence monitoring is accomplished by periodic "walkovers" of recently mined <br />areas within the present permit area. Walkovers are generally done in conjunction with <br />survey monitoring due to the seasonal accessibility of the area. During the 2011 <br />monitoring season, visual monitoring consisted of visual inspections done while <br />performing survey monitoring and water monitoring. <br />Visual monitoring is concentrated over areas of retreat mining with particular emphasis <br />on areas mined under low overburden. Since the mine has now been idled in excess of <br />10 years, there are no areas of particular emphasis on which to concentrate visual <br />inspections. <br />Projected Subsidence Impacts - 2012 <br />Subsidence impacts during 2012 are projected to be minimal based upon subsidence <br />patterns established to date. No mining is currently projected for 2012. <br />1 <br />